Honor guards stand in front of caskets prior to a memorial service for first responders who died in last week's fertilizer plant explosion in West, Texas, on Thursday, in Waco, Texas.

President Obama, Texas Gov. Rick Perry, and firefighters from across the country were among those who paid tribute at a packed memorial service to the victims of a Texas fertilizer plant blast that killed 14 people on April 17, many of whom were first responders.

The deadly plant explosion decimated part of the small Texas city of West, with a population of only about 2,800. More than 200 people were injured in the blast; 12 who died were volunteer firefighters.

"These are volunteers: Ordinary individuals blessed with extraordinary courage," Gov. Perry said at Thursday's service. "They knew full well that another explosion was a possibility."

Caskets draped in large American flags were lined up in the front of the memorial, which was being held at Baylor University in Waco, located about 20 miles from West. The memorial was comprised of speeches from officials, as well as videos of victims' families and friends, who shared memories of their loved ones.

"We need people who so love their neighbors as themselves that they’re willing to lay down their lives down for them," he said. "America needs towns like West."

Speaking at the memorial service for West, Texas,' fallen first responders, President Obama praised the "selfless" acts of the volunteers who went to fight the blaze at the fertilizer factory.

In the videotaped eulogies, relatives shared how those who died were passionate about protecting the people of West.

"Words cannot express how much I'm going to miss my husband. He was my everything," said Kelly Pustejovsky, wife of Joey Pustejovsky, a member of the West volunteer fire department who was killed, in a video broadcast during the service.

Six of Pustejovsky's other relatives spoke in the video too, including his grandmother, who laughed through her tears about her grandson's love of fried chicken, and said she knew he was in heaven now.

Obama said, "I cannot match the power of the voices you just heard on that video, And no words adequately describe the courage that was displayed on that deadly night ...What I can do is offer the love and support and prayers of the nation."

He also noted that last week was filled with overwhelmingly horrific news events, between the Boston bombings and the deadly blast in Texas.

"While the eyes of the world may have been fixed far away, our hearts were also here," he said.

The service was hosted by the National Firefighters Foundation. Chief Ronald Siarnicki, executive director of the foundation, told mourners, "This disaster happened last week, but we know the ground is still shaking, and will be for a long time."

"It could not break this community," Siarnicki said. "Remember this: Come tomorrow or the next day or anywhere from here on out, you are not alone, because the fire service will be here for you."

The large crowd inside Baylor was dotted with people wearing T-shirts that read, "God bless West."

Before the memorial, 1,000 firefighters from across the U.S. held a half-mile-long procession in Waco to honor the fallen firefighters.

Investigators have located a 93-foot-wide and 10-foot-wide deep crater where the central Texas explosion happened, but still don't know what caused the blast.

A 15th person who was injured in the blast — a 96-year-old man — succumbed to his injuries the following day, according to NBCDFW.com.

Meanwhile, on Monday, the first individual lawsuit was filed as a result of the explosion. A single mom who lived next door to the West Fertilizer plant is seeking up to a million dollars after she and her 14-year-old son "lost all their worldly possessions," the suit says.

Drinking water in West is still not potable more than a week after the chemical fertilizer blast. Residents have boiled their water since the explosion, which shook the ground so much, it registered as a 2.4-magnitude earthquake.